Essentially what the challenge is trying to prove is that Prop 8 is Unconstitutional. Yes, Federally Unconstitutional. The opponents of Prop 8 who brought this lawsuit, contend that the US Constitution does not allow any single group, racial, religious, or a particular sexual orientation, to be discriminated against. Prop 8 discriminates! Regardless of what the Court in California rules, this will likely be appealed to the US Supreme Court, which could make all state laws forbidding same-sex marriage invalid.
Keep up the fight!